I've seen different methods in different textbooks for this. I'm wondering how a GCSE student would tackle it and what their answer would be.

Find the interquartile range of this set of data:

1,2,3,5,7,9

What answer would you get? I would think most people will get one of the two answers below:

Spoiler:

Show

5 or 6.5

I'm currently teaching a yr 9 class IGCSE material where finding the IQR of ungrouped data doesn't seem to be in the syllabus. It doesn't really matter which method I teach them, I'm just interested in how it's taught in the UK.

(Original post by notnek)
I've seen different methods in different textbooks for this. I'm wondering how a GCSE student would tackle it and what their answer would be.

Find the interquartile range of this set of data:

1,2,3,5,7,9

What answer would you get? I would think most people will get one of the two answers below:

Spoiler:

Show

5 or 6.5

I'm currently teaching a yr 9 class IGCSE material where finding the IQR of ungrouped data doesn't seem to be in the syllabus. It doesn't really matter which method I teach them, I'm just interested in how it's taught in the UK.

(Original post by notnek)
If the position found is a fraction, I've seen most textbooks round to the nearest integer or find the mean of the two numbers whose positions are the floor and ceiling of the number.

In edexcel S1 they round to the nearest integer, i don't know about GCSE.

(Original post by notnek)
If the position found is a fraction, I've seen most textbooks round to the nearest integer or find the mean of the two numbers whose positions are the floor and ceiling of the number.

Is the method that math12345 gave the standard way it is taught at GCSE?

I am not worrying about it, i am preparing for physics which is on Thursday, S1 is on Friday so i will prepare for it on Thursday. Hopefully an easy probability question will come up

Though one thing has got me worrying, someone today said that the best way to prepare was to learn all the mark schemes, i am not doing this, i will just attempt 1 past paper and just see the answers from the mark scheme, will i get good marks?